Vishnu
Vishnu is a major Hindu god and the protector of the cosmos. He is the peace--loving deity of the Hindu Trinity, and the sustainer of life with his steadfast principles of order, righteousness and truth. When these values are under threat, Vishnu emerges out of his transcendence to restore peace and order on earth. The Vishnu Sahasranama (the thousand names of Vishnu) call him the Paramatman (the eternal soul) and the Parmeshwar (eternal god). he is commonly known as Narayana or Hari. Vishnu is the All-Pervading essence of all beings, the master of—and beyond—the past, present and future, one who supports, sustains and governs the Universe and originates and develops all elements within. This illustrates the omnipresent characteristic of Vishnu. Vishnu governs the aspect of preservation and sustenance of the universe, so he is called "Preserver of the universe". His eternal or permanent abode beyond the material universe is Vaikuntha which is a realm of eternal bliss and happiness. It is also known as Paramdhama, which means final or highest place for liberated souls, where they enjoy eternal bliss and happiness. Vaikuntha is situated beyond the material universe and hence, can not be perceived or measured by material science and logics. His other abode within the material universe is Ksheer Sagara, where he reclines and rests on Shesha. It is known to be the topmost realm in the material universe, even higher than Satyaloka where Brahma resides. Vishnu manages and sustains the universe from there. Hence, Ksheer Sagara is also sometimes known as local Vaikuntha of the material universe, which is approachable by demigods in order to meet the lord in case of any emergency or disturbance in universal balance. Etymology The traditional explanation of the name Viṣṇu involves the root viś, meaning "to settle" (cognate with Latin vicus, English -wich "village", Slavic: vas -ves, or also (in the Rigveda) "to enter into, to pervade", glossing the name as "the All-Pervading One". An early commentator on the Vedas, Yaska, in his Nirukta, defines Vishnu as vishnu vishateh "one who enters everywhere", and yad vishito bhavati tad vishnurbhavati, "that which is free from fetters and bondages is Vishnu". Mythology and religion As stated in the Bhagawat Gita, whenever evil ascends onto the earth, Vishnu incarnates to protect and liberate it. All incarnations of god are therfore attributed to Vishnu, because he is the presever. The list of his incarnations vary. The most common and accepted version is that of ten; out of which nine have already taken place, while the tenth one is yet to come. in some we come accross a list of twenty three, with the names of Ved Vyasa and Satvata present. The ten main incarnations also differ, though the common version is Matsya (the fish), Kurma (tortoise), Varaha (boar), Narasimha (the lion-man hybrid), Vamana (the dwarf), Parashurama (the Rama with an axe), Rama (the prince of Ayodhya), Krishna (the dark-skinned cowherd), Balarama (the Rama of might) and Kalki (the destroyer). Some replace Balarama with Buddha. Dashavatara Matsya The first of the incarnations is the fish Matsya, who saved the world from a flood and killed the demon Hayagriva, who had stolen the Vedas from Brahma. Matsya was caught one day by King Satyavrata, who kept him in a glass bowl. The next day, it had grown to double its size, and Satyavrata transported it to a well. In a short time, it grew too big for the well. Satyavrata released it into the sea and saw it grow larger, till it was the size of a whale. Astonished by the fish's growth, Satyavrata realized that the fish was the god Vishnu. Vishnu as Matsya reveals his real identity and informs Satyavrata that a pralaya (doomsday) would soon come as a yuga (epoch) and a kalpa (aeon equal to Brahma's day) would soon end. Brahma sleeps in his night and his creation dissolves, submerging the earth and all the other worlds in the cosmos in the primeval ocean. Vishnu promises to return to rescue Satyavrata at the time of pralaya and orders him to bring all living creatures and seeds of all trees on a boat, which the gods would gift him. As pralaya came, Matsya came and pulled the boat with the serpent Shesha as the rope, fastened to his horn. As Matsya swam through the flood waters, he discoursed the king on various topics and revealed to him knowledge of the Vedas, Puranas, Samhitas as well as the Supreme Truth. After last wave of the flood ended, Matsya slew Hayagriva and rescued the Vedas and handed them over to Brahma, who woke after his night. Kurma Purana scripture indicates that the sage Durvasa had given a garland to Indra, the king of Gods. Indra placed the garland around his elephant, but the animal trampled it, insulting the sage. Durvasa then cursed the gods to lose their immortality, strength, and divine powers. After losing the kingdom of heaven, they approached Vishnu for help. He advised that they drink the nectar of immortality to regain their glory. To obtain it, they needed to churn the ocean of milk, a body of water so large they needed Mount Mandara as the churning staff, and the serpent Vasuki as the churning rope. The Devas were not strong enough to churn on their own, and declared peace with their foes, the Asuras, to enlist their help. Finally, Mount Mandara churned, but the force was so great the mountain began to sink into the ocean of milk. Taking the form of the turtle Kurma, Vishnu bore the mountain on his back as they churned the waters. Fourteen precious things arose from the turbulent ocean, culminating with Dhanvantari, the physician of the gods, who brought with him the nectar of immortality. Varaha When a demon named Hiranyaksha dragged the earth to the bottom of the sea, Vishnu took the form of a boar in order to rescue it. They fought for a thousand years. Then Varaha slew the demon and raised the earth out of the water with his tusks. The myth reflects an earlier creation legend of Prajapati (Brahma), who assumed the shape of a boar in order to lift the earth up out of the primeval waters. Narasimha The demon Hiranyakashipu, twin brother of the demon overthrown by Vishnu in his previous incarnation as Varaha, obtained a boon from the god Brahma that he could not be killed by man or beast, from inside or outside, by day or by night, and that no weapon could harm him. Thus, feeling secure, he began to trouble heaven and earth. His son, Prahlada, on the other hand, was a devotee of Vishnu, even though his father threatened his life because of it. One day the demon challenged Prahlada and, kicking a stone pillar, asked: “If your god is omnipresent, is he in this pillar also?” Vishnu emerged from the pillar in the form of a man-lion and slew the demon at dusk on the threshold. Vamana Vishnu descended as the Vamana avatar to restore the authority of Indra over the heavens, as it had been taken by Mahabali, a benevolent Asura King. Bali was the grandson of Prahlada, the son of Hiranyakshipu. Vamana, in the guise of a short Brahman carrying a wooden umbrella, went to the king to request three paces of land. Mahabali consented, against the warning of his guru, Sukracharya. Vamana then revealed his identity and enlarged to gigantic proportions to stride over the three worlds. He stepped from heaven to earth with the first step, from earth to the netherworld with the second. King Mahabali, unable to fulfill his promise, offered his head for the third. Vamana then placed his foot and gave the king immortality for his humility. In worshiping Mahabali and his ancestor Prahláda, he conceded sovereignty of Pátála, the netherworld. Some texts also report that Vamana did not step into the netherworld, and instead gave its rule to Bali. In giant form, Vamana is known as Trivikrama.